I just got a psone and nintendo64, I'm looking to pick up a snes and nes. Any suggestions as far as video setup goes? I know the nes and snes will look best on an older CRT, but what about the psone and nintendo 64? Will those two look ok on an LCD HDTV?
Nope. Those are both 480i devices. They will look like crap and be blocky, blurry, and jerkey scaled and processed up to 1080p. Basic rule of thumb is if it doesn't have native component or HDMI output and at least 480p, it's too old to expect a decent image on a HD flat panel. Generally this is anything before PS2/XBox/Game Cube.
Best possible display for 480i and older consoles will be via SCART RGB cables and a Sony PVM series monitor in the 20-25" range with a SCART to RGB + composite sync 4 x BNC adapter. This will give you the purest best possible image that will rival brand new arcade CRT monitors.
I'd take a picture of my SNES on my PVM-20M4U on RGB, but it's hard to get an image that isn't washed out by flash, distorted by reflections in the glass of the tube, moire patterns, or over exposed and bloomed to hell with the flash off. Even when I do get a decent picture it doesn't do it justice.
Those monitors are the absolute best thing you can get. They are old multi thousand dollar professional studio monitors that you can pick up for like $50 now. Basically the last and best RGB/NTSC CRTs ever made (unless you count like the Sony F500R PC monitor but that's a VGA monitor not a "video" monitor).
The PVM-20M4U takes RGB, component, s video, external sync, sync on green, composite video sync, anything you can throw at it, has a .30 something aperture grill pitch and 800 TV lines, back in the 1990s before HDTV and LCD/plasma/DLP/etc. Even shitty NTSC composite looks lightyears better on one of these things vs a standard TV... but RGB is just breath taking.
Paid $140 shipped for my 20" PVM which is on the high side but it's basically brand new with 100 hours on it. If you can, snag up a PVM 2530 (25") or even a 2950Q (29") if you can get one locally (see these all the time on Ebay for like $50 but local pickup only).